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Working With a Proportional Flow System?

Save yourself some work and have a bit of fun.

Easy-to-use Excel spreadsheets and instructions only $10.

Sheet 1 provides a zone-by-zone output table with surface temperature at various outside temperatures. (Requires input from a good heat loss calculation).

Sheets 2-3 allow you to determine system return temperature and delta-t, thus establishing an idealized reset curve. These are similar to the sheets I currently posted here, but have an extra input (r-value) for use with radiant panels.) You can easily optimize for low supply temperature, low flow and high delta-t.

TRVs required for larger and/or non-ideally balanced systems. FHVs (similar to TRVs but for radiant panels) required for radiant panel use. (Zone flows will GREATLY aid you in balancing the FHVs.)

Will work for: iron rads, panel radiators, tube-in-slab, HEAVY conduction plates, Warmboard, any reasonable floor covering.

Only $10 including postage. All material on CD. Requires ability to read/modify Excel spreadsheets and basic use knowledge of such programs. Instructions in Word documents and .pdf files.

Allows full zoning of spaces with even poor radiation balance and different heat transfer mechanisms using only a single, small system circulator. Primary/secondary NOT required with some boilers.

Even if you're not using TRVs you'll see just what they can do for you.

"Stock" data provided (including output sheet published here MANY years ago) just happens to mirror the specs of the 6-24 Vitodens. Reset curve idealized for constant delta-t just happens to find 1.3 gpm near WWSD and 141° supply temp at design. Proceeds devoted to buying my own.

Contact Mike Thies, [email protected] (573) 651-0770, (573) 651-8601 FAX
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